This invention is directed to an electro-photographic printer and, in particular, to an electro-photographic printer utilizing a liquid crystal cell which operates as a light valve.
The recent advancement in semiconductor technology has caused a substantial reduction in the cost of central processing units, memories and the like for computers. This progress allows many more consumers to purchase and operate such systems and to learn how to use micro-computers and office computers, as well as printers which print out from these computers. Accordingly, the present advance in technology benefits not only specialists in electronic data processing systems (EDPS) but also the general consumer. Hence, improved output printing systems which can print out ordinary documents as well as documents having Chinese characters or Japanese letters are presently needed.
A typical example of an output printing system for a computer or the like is a Japanese word processing system. The printer utilized as an output terminal for the output system of a computer requires a resolution on the order of 32.times.32 dots for printing Chinese characters or the like. Such a printer is required to have a high resolution and a high speed without sacrificing one for the other.
At the present time, an electro-photographic printer utilizing a laser or optical fiber tubes (OFT), or a multi-stylus electrostatic printer are in use. However, these printers are extremely expensive and accordingly increase the manufacturing cost of the data output system. The expensive cost retards the spread of various output systems to the general market in spite of the market need therefor. This is also basically true with respect to high speed facsimile printers, cathode ray tube (CRT) hard copiers, and terminal equipment of several varieties. Accordingly, an electro-photographic printer having a high resolution, a high quality printing and a high printing speed, yet reduced in cost, is extremely desired.